A tablet computing device commonly allows users to make various gestures by touching the surface of the device's touchscreen in a prescribed manner. For example, a user can instruct the computing device to execute a panning operation by touching the surface of the touchscreen with a single finger and then dragging that finger across the surface of the touchscreen surface. In another case, a user can instruct the computing device to perform a zooming operation by touching the surface of the touchscreen with two fingers and then moving the fingers closer together or farther apart.
To provide a robust user interface, a developer may wish to expand the number of gestures that the computing device is able to recognize. However, a developer may find that the design space of available gestures is limited. Hence, the developer may find it difficult to formulate a gesture that is suitably distinct from existing gestures. The developer may create an idiosyncratic and complex gesture to distinguish over existing gestures. But an end user may have trouble remembering and performing such a gesture.